Method of and machine for forming seamless tubing



June 22 1926 E.. C. RIEBE METHOD OF AND MACHINE FOR FORMING SEAMLESS TUBING.

2 Sheets-Sheet N M @W Y $6 n 8 1 I Nb i i n m 3 8 Am 5 an T NQWQ INVENTOR (I 7 65,

ATTORNEYS E. C. RlEEsE"v METHOD OF AND M'ACHINE FOR EUEM ING? S EAMLETS-S TUBING F'iled' June 1.8, 1925. 2'1 Shams-Sheet 2 INVENTOR (E66,

ATTORNEYS Patented June 22, 1926.

UNITED STATES PATENT OFFICE.

EDGAR C. IRIEBE, 0F PARIS, FRANCE.

METHOD OF AND MACHINE FOR FORMING SEAMLESS TUBING.

Application filed June 18, 1925; Serial No. 38,115.

less time for a tube of the same size than is possible by means of any machine and method known prior to the invention.

A still further object of the invention is the provision of a machine and method whereby a seamless metallic tube can be accurately formed to have a less inner diameter than is possible by means of any prior machine or method.

Other objects and advantages of the invention will be apparent from the following description, considered in conjunction with the accompanying drawings, in which Figure 1 is a view mainly in side elevation and partly in vertical section, showing a machine embodying the invention,

Figure 2 is an end view of the structure exhibitedin Figure 1,

Figure 3 is a plan view of a portion of the machine exhibited in Figures 1 and 2, and

Figure 4 is a perspective View of the mandrel of the machine.

The supporting structure of the machine comprises a base 1 which is rigidly secured to a foundation 2 or is supported in any other suitable known manner. The base 1 is-formedwith a pair ofupstanding portions 3 and 4 respectively spaced longitudinally of the base, the upstanding portion 3 being shown as being located at one end of the base while the upstanding portion 4 is located intermediate the length of the base.

The upstanding supporting portions 3 and 4 carry horizontally aligned bearings 5, 6 respectively through which a shaft or tree 7 extends and by means of which the shaft or tree 7 is rotatably supported. A bracket 8 is secured on the base 1 adjacent the end of the latter which is opposite the upstanding ortion 3. This bracket 8 has an upstan ing plate portion 9 formed with an openin 10 in axial alignment with the shaft 7 an close to the adjacent end of the latter. A tubular matrix 11 has a flange 12 at its inner end secured by fastening devices such as the bolts and nuts indicated at 13 to the upstanding plate portion 9 of the bracket 8 so that the bore of the matrix 11 is in axial alignment with the opening 10 and an opening 14 in the body of the matrix 11 is at the upper side of the latter. A hopper 15 having a lining 16 of refractory material is supported on the base by means of standards 17 in position to discharge through the opening 14 into the space within the tubular matrix 11.

. A mandrel indicated generally at 18 comprises a relatively large bearing portion 19 which is journaled in the inner end portion of the tubular matrix 11, whereby themandrel will be rotatably supported in concentric relation to the tubular. matrix. The mandrel 18 is connected detachably to the shaft 7 to rotate with the latter when the shaft 7 is rotated in one direction by means of a reduced threaded inner end portion 20 of the mandrel which protrudes from the opening 10 of the supporting plate 9 beyond the inner face of the-plate 9 and is engaged with a threaded axial socket 21' in the adjacent end ofthe shaft 7. The major portion of the mandrel 18,indicated at 22, extends from the bearing portion 19 to the outer end of the mandrel and 'is of less diameter than thebearing portion 19, whereby the portion 22 of the mandrel will be disposed in spaced concentric relation to the inner wall of the tubular matrix 11. The portion 22 of the mandrel is formed with a network of ridges, comprising a threadlike ridge 23 having convolutions of slight pitch extending spirally of the mandrel from the outer end of the portion 22 to the bearing portion'l9 and spaced ridges 24 which extend longitudinally of the portion 22 of the mandrel and intersect the convolutions of the thread-like ridge 23.

The mandrel 18 is provided with an axial bore 25 which extends the entire length thereof and is in alignment and communication with av bore 26 which extends axially through the shaft 7. The end portion of the shaft 7 be reduced as indicated at 27 and is received "in a stutfing box 28. The latter may be supported on an end shelf 29 at the upper end of the supporting portion 23 of the base and includes a combined packing gland and coupling plate 30 having a nipple 31 at its outer side in communication through an opening 32 with a tubular boss 33 at its inner side,

the reduced end portion 27 of the shaft 7 terminating in the tubular boss 33, whereb the nipple 31 will be in communication with the bore 26 of the shaft 7. A conduit 34 has an end portion secured on the nipple 31 and is adapted to conduct compressed air from any suitable source of supply to the bore of the shaft 7 and thence to the bore of the mandrel 18 for a purpose to be presently stated.

From the foregoing description of the various arts of the device, the operation thereo may be readily understood. The shaft may be rotated in the direction indicated by the arrow in Figure 1 in any suitable known manner as by means of,a

torque imparted thereto from a motor, not shown, through suitable motion transmis- SlOIl mechanism, not shown, to the pulley 35. The mandrel 18 and'the tubular matrix -11 are made of heat resistant steel or like metal. The mandrel and the matrix first are heated in any suitable known manner, the shaft 7 then is rotated in the direction indicated and then molten metal from which a length of seamless tubing is to be made 1s poured through the hopper 15 into the space between the mandrel and the inner wall of the matrix. The rough outer surface of the portion 22 of the mandrel will engage with the molten metal as the mandrel rotates and the molten metal will bepushed in the form of, a tube 36 from the free end of the matrix 11. Compressed air passes through the shaft 7 and the mandrel 18 into the tube 36 as the latter is pushed from the mandrel beyond the free end of the matrix 11 and assures quick hardening and coolmg of the body of the tube 36. A suitable conveyor, not shown, such as an endless chain conveyor preferably is provided at the free end of the matrix 11 for supporting the tube 36 as it is pushed from the matrix and for moving the tube 36 axially from the matrix without permitting any lateral stress on the tube 36. In the event that the shaft 7 is driven by direct connection with driving means carried by the base 1, the shaft 7 and the matrix 11 may be inclined downwardly toward the free end of the latter and a chain conveyor or the like may be dispensedwith, the tube 36 sliding along a trough in: anfinclined table, not shown, which may be provided at the free end of the matrix.

The thickness of the tube that is to be 3 formed of molten metal in the manner .de-

of any devary according to the outer diameter of t e len h of seamless tubing which is to be forme as a result of a particular operation of the machine.

I claim 1. A machine for use in forming seamless metal tubing comprising a tubular matrix having a feed openin for molten metal in its upper side, a man rel mounted to rotate in said matrix, said mandrel and said matrix being cooperatively formed to close the bore of the matrix at one end of the latter, said mandrel having a portion extending in the matrix past said feed openmg in spaced concentric relation to the inner wall of the matrix, said portion of the mandrel having means on its periphery operable. on rotation of the mandrel to force metal from the between the mandrel and the matrix one end of the matrix in the form of a tube,

sfpace rom said mandrel having an axial bore extend- I ing the full length of the mandrel.

2. A machine for use in forming seamless metal tubing comprisin a tubular matrix having a feed openin or molten metal in its upper side, a man rel mounted to rotate in said matrix, said mandrel and said matrix bein cooperatively formed to close the bore of t e matrix at one end of the latter, said mandrel having a portion' extending in the matrix past said feed opening in spaced concentric relation to the inner wall of the matrix, said portion of the mandrel having a thread on its periphery extendin spirally in convolutions of slight pitch and adapted when the mandrel is rotated to engage with the molten metal and to push the molten metal from the matrix in the form of a tube, said mandrel havingan axial bore through which compressed air may be forced and discharged from said extending end of the mandrel.

3. A machine for use in forming seamless metal tubing comprisin a tubular matrix having a feed openin or molten metal in its upper side, a man rel having a bearing portion journaled in the end portion of the matrix and having a reduced end portion extending past said feed opening in spaced parallel relation to the inner wall of the matrix, said mandrel having an axial bore, a drive shaft coupled endwise to said mandrel, said drive shaft having an axial bore in alignment with the bore of the mandrel and shaft which is remote from said mandrel for supplying compressed air to the bore of said shaft, as and for the purpose described.

4. The herein described method of forming seamless metal tubing which comprises feeding molten metal to the space between two spaced. concentric tubular members so that the metal willbe forced in tubular form from said space at one end' of the space, and then forcing air through the in- 0 her tubular member into the ,tube that is forced from said space.

EDGAR c. RIEBE. 

